Stenosis grading from contrasted x-ray angiograms is of major interest for minimally invasive treatment of diseased coronaries in the cardiac cathlab. Obstructed volume flow and increased pressure decline at a coronary lesion are the major cause of coronary heart disease. For a well founded treatment decision, it is important in daily clinical routine to assess the severity of such stenoses. Currently, subjective visual inspection of coronary angiograms or the determination of the pressure decline using an intravascular pressure gauge are used to assess this severity. Coronaries move with heart beat and respiration of a patient such that a separation between the movement of the vessels themselves and the flow of blood inside the vessels is required for a clinically valid assessment.